In demonology Valac is a mighty Great President of Hell, having thirty (thirty-eight to other authors) legions of demons under his command. He gives true answers concerning hidden treasures and where serpents may be seen, which he puts into the conjurer's hands completely strengthless.

Valac is depicted as an angel-winged boy riding a two-headed dragon.

Other spellings: Ualac, Valak, Valax, Valu, Volac.

See also The Lesser Key of Solomon, Ars Goetia.